The present invention relates generally to cable ties, and more particularly to ball-type locking ties.
Ball-type locking heads are well-known for use in metal cable ties for providing high tensile strength bundling capability. In addition to typically having a higher tensile strength than plastic ties, metallic ties also tend to be less brittle and deformable when exposed to extreme temperatures, humidity, corrosive elements, and radiation. An example of a metal cable tie having a ball-type locking head is seen in U.S. Pat. No. 4,399,592.
As shown in the ""592 patent, a typical metal cable tie may have a metallic band, one end of which is joined to a metallic locking head for receiving and retaining the other end of the band to bundle objects together. A metallic ball or roller means is captively held in the head for lockingly engaging the band. The ball is shiftable between a threading position wherein it is disposed relatively closer to the end of the head from where the threaded band emerges and a locking position wherein the ball is relatively closer to the end of the head into which the free end of the band is inserted. The tie will typically include band deflection structure for bending a portion of the band proximate the ball so as to permit the ball to rotate or slide over the band as the band is threaded forwardly through the locking head but also to force or wedge the ball into the locking position whereby it frictionally restricts unthreading of the band when backward force is applied to the band. In this manner, the band may be forwardly threaded to tightly bind together multiple objects and the ball-type locking head will prevent unthreading while maintaining high resistance to tensile failure.
Cable ties of the type disclosed in the ""592 patent have come to have numerous useful applications. However, some applications calling for high tensile strength or other desirable qualities of the metal ball-type locking ties present a sporadic or regular need for unbinding the multiple objects. Typical metal ties have drawbacks in such situations because they must be cut, and thereby permanently destroyed, in order to remove them from their respective bundles. Thus, in order to re-bundle the objects, an entirely new cable tie would have to be applied, the former one not being reusable after being cut. Further complicating this process is the fact that cutting a metal band typically requires a tool that may not be on-hand or conveniently retrieved from the location of the tie.
Thus, there is a need for a cable tie having many or all of the performance qualities of prior metal ball-type locking cable ties while including the additional quality of being easily releasable and/or reusable.
To address this shortcoming in prior metal cable ties, a new cable tie is disclosed for releasably bundling together a plurality of elongated objects. The cable tie includes an elongated band for circumscribing the plurality of elongated objects, the band having first and second opposed ends. The cable tie further includes a locking head disposed generally on the first end of the elongated band. The locking head includes a chamber defined within the locking head, a chamber entry and exit for permitting the band to be moved forwardly through the chamber by inserting the second end of the band into the entry and urging the band in a forward direction through the chamber such that the second end of the band emerges from the exit and for permitting the band to be further moved beyond the chamber in the forward direction after the second end of the band has emerged from the exit by further forward urging of the band. The locking head further includes an appropriately dimensioned ball disposed within the chamber such that the ball may assume one of at least two positions within the chamber, the ball assuming a first, generally free position when the band is being forwardly urged through the chamber and a second, generally restricted position when the band is being backwardly urged through the chamber. When the band is being forwardly urged through the chamber the ball is disposed in the first, generally free position within the chamber and does not frictionally restrict the band in response to the forward urging, thereby permitting forward movement of the band through the chamber. When the band is being backwardly urged through the chamber the ball is disposed in the second, generally restricted position, thereby frictionally restricting the band from substantial backward movement through the chamber in response to the backward urging. There is also an opening in the locking head chamber for providing access to the ball by an implement such that the implement may be used to urge the ball from the second, generally restricted position toward the first, generally free position whereby the band may be urged backwardly and thereby moved backwardly through the chamber without the ball frictionally restricting the backward movement of the band as it would in the absence of the implement.
Also disclosed is a locking head for use with a cable tie for releasably bundling together a plurality of elongated objects. The cable tie includes an elongated band for circumscribing the plurality of elongated objects and having first and second opposed ends. The locking head includes a chamber defined within the locking head, a chamber entry and exit for permitting the band to be moved forwardly through the chamber by inserting the second end of the band into the entry and urging the band in a forward direction through the chamber such that the second end of the band emerges from the exit and for permitting the band to be further moved beyond the chamber in the forward direction after the second end of the band has emerged from the exit by further forward urging of the band. An appropriately dimensioned ball is disposed within the chamber such that the ball may assume one of at least two positions within the chamber, the ball assuming a first, generally free position when the band is being forwardly urged through the chamber and a second, generally restricted position when the band is being backwardly urged through the chamber. When the band is being forwardly urged through the chamber the ball is disposed in the first, generally free position within the chamber and does not frictionally restrict the band in response to the forward urging, thereby permitting forward movement of the band through the chamber. When the band is being backwardly urged through the chamber the ball is disposed in the second, generally restricted position, thereby frictionally restricting the band from substantial backward movement through the chamber in response to the backward urging. There is also an opening in the locking head chamber for providing access to the ball by an implement such that the implement may be used to urge the ball from the second, generally restricted position toward the first, generally free position whereby the band may be urged backwardly and thereby moved backwardly through the chamber without the ball frictionally restricting the backward movement of the band as it would in the absence of the implement.
Also disclosed is a system for releasably bundling together a plurality of elongated objects. The system includes
a cable tie having an elongated band for circumscribing the plurality of elongated objects, the band having first and second opposed ends. The system also includes a locking head disposed generally on the first end of the elongated band, the locking head including a chamber defined within the locking head, a chamber entry and exit for permitting the band to be moved forwardly through the chamber by inserting the second end of the band into the entry and urging the band in a forward direction through the chamber such that the second end of the band emerges from the exit and for permitting the band to be further moved beyond the chamber in the forward direction after the second end of the band has emerged from the exit by further forward urging of the band. An appropriately dimensioned ball is disposed within the chamber such that the ball may assume one of at least two positions within the chamber, the ball assuming a first, generally free position when the band is being forwardly urged through the chamber and a second, generally restricted position when the band is being backwardly urged through the chamber. When the band is being forwardly urged through the chamber the ball is disposed in the first, generally free position within the chamber and does not frictionally restrict the band in response to the forward urging, thereby permitting forward movement of the band through the chamber. When the band is being backwardly urged through the chamber the ball is disposed in the second, generally restricted position, thereby frictionally restricting the band from substantial backward movement through the chamber in response to the backward urging. There is also an opening in the locking head for providing access to the ball. The system also includes an implement for being inserted generally into the opening and thereby urging the ball from the second, generally restricted position toward the first, generally free position whereby the band may be urged backwardly and thereby moved backwardly through the chamber without the ball frictionally restricting the backward movement of the band as it would in the absence of the implement.